1. Field of the Invention
The invention relates to an image forming apparatus and an image forming system in which a woven pattern is formed on a record medium together with image creation data and, more particularly, to an image forming apparatus and an image forming system in which a coloring agent that is used for image creation is properly consumed.
2. Description of the Related Arts
In an image forming system having a user terminal, a document server for storing documents to be printed, and an image forming apparatus such as a printer for receiving print data (that is, image creation data) of document contents transmitted through the user terminal and printing, the image forming apparatus prints the print data onto a sheet as a record medium by using, for example, toner or ink as a coloring agent.
For the printed sheet, in order to suppress a copy, forgery, leakage of security, or the like of the print data, together with the print data, the following pattern is printed as a security pattern (i.e. a woven pattern) to suppress an illegal use onto the whole surface of the sheet as a background of the print data: a hidden pattern based on a character image such as “Copy Prohibition”; a watermark based on character information such as “Company Secret”; a leakage suppression pattern based on information including the user and the like; or the like.
Such a security pattern has been disclosed in, for example, JP-A-1999(Heisei 11)-298717.
However, the coloring agent is consumed in order to print the security pattern. Particularly, in the conventional image forming system, since the image forming apparatus uniformly prints the security pattern to all print documents which are stored into the document server, a large amount of coloring agent is consumed.